CVE-2026-71271
Memos Webhook SSRF via 0.0.0.0 Reserved-IP Bypass
CVSS Score
8.5
EPSS Score
0.0%
EPSS Percentile
0th
Memos' webhook URL validation, isReservedIP() (internal/webhook/validate.go), checks a candidate IP against a reservedCIDRs list that omits 0.0.0.0/8 and never calls ip.IsUnspecified() — unlike the correctly implemented sibling function isInternalIP() in internal/httpgetter/html_meta.go, which does. Because Linux redirects connections to 0.0.0.0 to loopback (127.0.0.1), an attacker registering a webhook URL of http://0.0.0.0:PORT/ bypasses the reserved-IP check and causes the Memos server to make outbound HTTP requests to its own loopback interface, exposing internal-only services.
| CWE | CWE-918 |
| Vendor | usememos |
| Product | memos |
| Published | Aug 5, 2026 |
Stay Ahead of the Next One
Get instant alerts for usememos memos
Be the first to know when new high vulnerabilities affecting usememos memos are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Affected Versions
usememos / memos
0 ≤ 0.29.1
References
Credits
Alibek Baxtiyorov